SOMETHING IS WRONG WITH MY TRUCK HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[Fit95]

CubanEvo- I have the same mods as you minus the mopar pcm and I feel like mine is low on power too. I haven't dynoed it though. I was in a half mile shootout and was outran by a 05 srt-10 with only a shifter in it. I'm more than disappointed with the money I spent on my mods for the lack of performance:argh: . Let me know what you find out. Thanks.

 

[Prof]

the reason i went to the other dyno was because they charged me $50 for 3 pulls Gaw charged me $120

Penny wise pound foolish...

Did you do your first dyno prior to the addition of the CAI, and mids?

If so you may still have a little fall off...or increase...there are lots of variables...temperature, humidity, heat soaked engine...dyno's are close estimates but they cannot control the environment.

 

[JTS VENOM PERFORMANCE]

Ok so i went to dyno my truck and here are the results I dynoed way more stock tahn with all my mods. What the hell could be wrong First dyno sheet is the one with mods and the second one was from when i was stock.

I NEED HELP GUYS PLEASE WHAT COULD BE GIVING ME THIS PROBLEM

first off you need to be on the same dyno for any kind of comparison

second swap back to the stock pcm and recheck.

also the jumpiness of the second dyno seems to be a problem with tire pressure, you should be around 30 psi to dyno, any higher and you can get spin, especially in hot conditions

 

[505'sFastestViper.]

the reason i went to the other dyno was because they charged me $50 for 3 pulls Gaw charged me $120

are you serious you drve a viper not a ford taurus!! 70$ difference come on now!!

 

[AWDisuzu]

I went through this criss cross at 5250 with somebody else a while back. When my dyno run, which didn't cross at 5250 was "corrected" to 5250, then reprinted, there was a ONE HORSEPOWER difference; that's it...

then it's wrong also. you can't simply "correct" something that was not calculated right in the first place. the formula is simple and I've never seen a dynojet plot the wrong numbers before unless the data was input wrong in the first place.

Actually, the Dynojet dyno can calculate horsepower even without a torque reading...

Using the formula, if you know horsepower you can calculate torque and vice versa without a dyno.

no, a dynojet can only measure one thing. torque. horsepower is derived from torque and is just a man made number. torque is real world measurement of twisting force. a dynojet can "plot" a hp graph but it's actually measuring torque and calculating HP.

that 2nd "base" dyno chart is off by a lot. If you lower the HP curve so that the lines cross at 5252 you'll see that the peak HP is more like 340 or 350 HP.

that's a lot more than 1 hp off. my buddy that runs the dyno I use told me that you can't mess up a dyno run this badly without doing it on purpose. perhaps he was trying to impress you with higher numbers?

 

[AWDisuzu]

good, because the first dyno isn't right anyway!

are you serious you drve a viper not a ford taurus!! 70$ difference come on now!!

 

[rottenronnie]

then it's wrong also. you can't simply "correct" something that was not calculated right in the first place. the formula is simple and I've never seen a dynojet plot the wrong numbers before unless the data was input wrong in the first place.



no, a dynojet can only measure one thing. torque. horsepower is derived from torque and is just a man made number. torque is real world measurement of twisting force. a dynojet can "plot" a hp graph but it's actually measuring torque and calculating HP.

that 2nd "base" dyno chart is off by a lot. If you lower the HP curve so that the lines cross at 5252 you'll see that the peak HP is more like 340 or 350 HP.

that's a lot more than 1 hp off. my buddy that runs the dyno I use told me that you can't mess up a dyno run this badly without doing it on purpose. perhaps he was trying to impress you with higher numbers?

Look under FORCE=MASS X ACCELERATION


http://www.bristoldyno.com/info/whatis.htm


The old Brake Dynos used the formula we are discussing.

 

[CubanEvo]

so you guys are telling me that both my dynos are wrong

 

[rottenronnie]

so you guys are telling me that both my dynos are wrong

Sorry about that.

I would go to the original dyno facility where you got your baseline do a few more pulls and go from there. Your newest dyno sheet looks a little funky...

 

[CubanEvo]

Sorry about that.

I would go to the original dyno facility where you got your baseline do a few more pulls and go from there. Your newest dyno sheet looks a little funky...

Ok


Hey what are some things i should do before i go to the dyno again and how lond shold i let my truck cool down.

 

[AWDisuzu]

What is your point? that does not change the fact that his dyno graphs are wrong. and from the page you used :

"There are a few common misconceptions concerning horsepower, torque, and the role they play in your engine and in your vehicle. For starters, they are not independent factors – the horsepower and torque numbers are mathematically linked with a formula: horsepower = torque X rpm / 5252. Therefore at any given rpm, if one knows the torque, one can calculate the horsepower, and vice-versa. In the automotive world, torque is strength and horsepower is the ability to perform work in a given amount of time. So, regardless of how badly one wants that high torque number, horsepower is what actually moves your car down the street or around the track, and horsepower is what tows trailers."

Look under FORCE=MASS X ACCELERATION


http://www.bristoldyno.com/info/whatis.htm


The old Brake Dynos used the formula we are discussing.

 

[AWDisuzu]

you don't have to let the truck cool down, but you do have to make sure the dyno operator inputs the correct values for your engine.

I always dyno my vehicles at normal temperature. sure, you will pick up a few extra horsepower on the dyno sheet with a cold engine but putting a cold engine under full throttle is going to wear it out faster or possibly damage it. Plus, that extra HP you see on the dyno with your cold engine will never be realized in real driving conditions.

good luck!

Ok


Hey what are some things i should do before i go to the dyno again and how lond shold i let my truck cool down.

 

[AWDisuzu]

Look under FORCE=MASS X ACCELERATION


http://www.bristoldyno.com/info/whatis.htm


The old Brake Dynos used the formula we are discussing.

there are no brake dynos in this discussion. the page you quote only mentions brake dynos once :

"I have an inertia-type chassis dynamometer. It measures the force and power that the spinning wheels of an automobile produce. It is not a "brake-type" dyno that measures the power that is actively absorbed by a water, oil, or eddy-current brake or by a generator."

 

[CubanEvo]

you don't have to let the truck cool down, but you do have to make sure the dyno operator inputs the correct values for your engine.

I always dyno my vehicles at normal temperature. sure, you will pick up a few extra horsepower on the dyno sheet with a cold engine but putting a cold engine under full throttle is going to wear it out faster or possibly damage it. Plus, that extra HP you see on the dyno with your cold engine will never be realized in real driving conditions.

good luck!

true:rock:

 

[rottenronnie]

What is your point? that does not change the fact that his dyno graphs are wrong. and from the page you used :

"There are a few common misconceptions concerning horsepower, torque, and the role they play in your engine and in your vehicle. For starters, they are not independent factors – the horsepower and torque numbers are mathematically linked with a formula: horsepower = torque X rpm / 5252. Therefore at any given rpm, if one knows the torque, one can calculate the horsepower, and vice-versa. In the automotive world, torque is strength and horsepower is the ability to perform work in a given amount of time. So, regardless of how badly one wants that high torque number, horsepower is what actually moves your car down the street or around the track, and horsepower is what tows trailers."

You seem absolutley focused on the 5252 formula which the DYNOJET DOES NOT USE TO CALCULATE IT'S RESULTS; (if you read the link I sent). That is my point.

I think we may be just confusing CubanEvo who is just looking for answers.

Like I said there was a ONE hirsepower difference when "adjusting" my pulls to 5250.

I think you and I went round with this before and I will stop here.

I recommended CubanEvo get another pull done at the original dyno facility.

 

[JTS VENOM PERFORMANCE]

Cubanevo call Jason and set up a day to have your truck dynoed, he is in sarasota fla, and you will get expert results, plus some expert advice on everything.
then there will be no questions of HP

http://www.heffnersperformance.com/

 

[AWDisuzu]

well, yes and NO. a dynojet measures HP and uses the formula to calculate torque. your website is misleading, as he was describing a situation where the dynojet may not pick up a good signal and so the measurement had to be fudged.

if you're truely interested in how a dynojet works, here is some text that explains it in easy language.

"First it is important to have an understanding of how DynoJet gets their horsepower numbers. Power in mechanical terms is the ability to accomplish a specified amount of work in a given amount of time. By definition, one horsepower is equal to applying a 550 pound force through a distance of 1 foot in one second. In real terms, it would take 1 HP to raise a 550 pound weight up 1 foot in 1 second. So to measure horsepower, we need to know force (in pounds) and velocity (in feet per second). Dynojet's inertial dynamometer measures power according to the terms just described. It measures velocity directly by measuring the time it takes to rotate two heavy steel drums one turn. It measures force at the surface of the drum by indirectly measuring it's acceleration. Acceleration is simply the difference in velocity at the surface of the drums from one revolution to the next. The force applied to the drums is calculated from acceleration using Newton's 2nd law, Force = Mass * Acceleration. Since the mass of the drums is know and acceleration has been measured, Power (horsepower) can now be calculated. Torque is then calculated using the horsepower number: Torque = Horsepower * 5252 / RPM."

You seem absolutley focused on the 5252 formula which the DYNOJET DOES NOT USE TO CALCULATE IT'S RESULTS; (if you read the link I sent). That is my point.

I think we may be just confusing CubanEvo who is just looking for answers.

Like I said there was a ONE hirsepower difference when "adjusting" my pulls to 5250.

I think you and I went round with this before and I will stop here.

I recommended CubanEvo get another pull done at the original dyno facility.

 

[Prof]

This thread is really interesting...I know nothing but am learning!

 

[rottenronnie]

This thread is really interesting...I know nothing but am learning!

I hope you are serious.:dontknow:

 

[dodgeff232]

What kind of dyno is it, and what was the temp that day? Heat can knock it off a lot